A neodymium (Nd) doped lithium-niobate-on-insulator (LNOI) was fabricated from a lithium niobate (LN) substrate diffusion-doped with Nd prior to the LNOI fabrication process. Diffusion doping enables the fabrication of differently doped regions on a single LNOI substrate, a key advantage for future applications in highly integrated photonics. Fluorescence spectra, emission cross-section, fluorescence lifetime, and small-signal gain of Nd:LNOI were determined for the first time to our knowledge and compared with data published for diffusion-doped ridge or channel waveguides in LN substrates. For an 11 mm-long sample, we achieve a small-signal gain for π (σ) polarization of about 14 (10) dB when pumping with a Ti:Sapphire laser, which is promising for future active components in Nd:LNOI like amplifiers and lasers.

中文翻译：

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绝缘体上掺钕铌酸锂 (LNOI) 的光学特性

在 LNOI 制造过程之前，由扩散掺杂有 Nd 的铌酸锂 (LN) 衬底制造了钕 (Nd) 掺杂的绝缘体上铌酸锂 (LNOI)。扩散掺杂能够在单个 LNOI 衬底上制造不同掺杂的区域，这是未来高度集成光子学应用的关键优势。据我们所知，Nd:LNOI 的荧光光谱、发射截面、荧光寿命和小信号增益是第一次确定，并与公布的 LN 衬底中扩散掺杂脊或通道波导的数据进行比较。对于 11 mm 长的样品，当使用 Ti:Sapphire 激光器泵浦时，我们实现了约 14 (10) dB 的 π (σ) 偏振小信号增益，这对 Nd:LNOI 等放大器中的未来有源组件很有希望和激光。